浅析火山渣轻骨料砌块墙裂缝的防止措施

针对火山渣轻骨料砌块墙体裂缝状况进行调查并结合试验研究,从火山渣轻骨料砌块本身质量及其影响墙体变形,如温度、干燥收缩等性能和施工方面角度,分析了火山渣砌块填充墙裂缝的成因以及相应的防止裂缝措施.     

高层建筑地下室混凝土墙体裂缝原因分析案例

高层建筑地下室混凝土墙体裂缝已经成为工程质量的一个通病。本文结合某高层地下室墙体裂缝情况进行分析讨论,提出该地下室墙体裂缝主要是混凝土收缩引起的,并进一步分析了引起收缩的原因是混凝土浇筑后拆模过早、没有保温措施、保湿养护不够,混凝土冷缩和干缩叠加等,从而造成墙体出现裂缝。     

利用火山渣轻骨料砌块分析在填充墙施工过程中存在的质量隐患

针对轻骨料火山渣砌块墙体裂缝状况进行调查并结合试验研究,从轻骨料火山渣砌块本身质量及其影响墙体变形如温度、干燥收缩等性能和施工方面角度,分析了火山渣砌块填充墙在施工过程中存在的问题以及相应的防止措施。     

利用火山渣轻骨料砌块分析在填充墙施工过程中存在的质量隐患

针对轻骨料火山渣砌块墙体裂缝状况进行调查并结合试验研究,从轻骨料火山渣砌块本身质量及其影响墙体变形如温度、干燥收缩等性能和施工方面角度,分析了火山渣砌块填充墙在施工过程中存在的问题以及相应的防止措施。     

轻骨料火山渣砌块在填充墙施工过程中存在问题的分析

针对轻骨料火山渣砌决墙体裂缝状况进行调查并结合试验研究,从轻骨料火山渣砌块本身质量及其影响墙体变形如温度、干燥收缩等性能和施工方面角度,分析了火山渣砌块填充墙在施工过程中存在问题以及相应的防止措施.     

对加气混凝土砌块墙体收缩裂缝的研究

加气混凝土砌块是利用工业废料生产的一种新型墙体材料,具有很多的特点,对其收缩性进行了系统的试验分析,并对其应用过程中的墙体收缩裂缝机理进行了研究.     

火山渣轻骨料砌块填充墙质量问题分析及解决措施

针对火山渣轻骨料砌块墙体裂缝状况进行调查并结合试验研究,从火山渣轻骨料砌块本身质量及其影响墙体变形如温度、干燥收缩等性能和施工方面,分析了火山渣砌块填充墙在施工过程中存在问题及相应的防止措施.     

轻钢泡沫混凝土墙体裂缝控制试验研究

轻钢泡沫混凝土复合墙体具有轻质、保温、隔声和防火等优良性能,但墙体易收缩开裂。为提高轻钢泡沫混凝土墙体的抗裂性能,对泡沫混凝土材料增加了构造措施和施工措施的轻钢泡沫混凝土墙体构件进行了试验研究。研究表明,在满足施工性能的基础上减少水胶比、添加纤维和轻骨料对减少泡沫混凝土收缩效果明显;采取在轻钢骨架两侧设置铁丝网或收口网、洒水覆膜养护和延长养护时间等措施,可有效控制墙体裂缝。     

轻骨料砌块框架结构填充墙在施工过程中存在质量隐患的控制

本文针对轻骨料火山渣砌块墙体裂缝状况进行调查并结合试验研究,从轻骨料火山渣砌块本身质量及其影响墙体变形如温度、干燥收缩等性能和施工方面,分析了火山渣砌块填充墙在施工过程中存在的问题并提出了相应的防止措施。     

陶粒火山渣轻集料砌块在框架结构施工中存在的质量隐患

本文针对轻集料陶粒火山渣砌块墙体裂缝状况进行调查并结合试验研究,从轻集料陶粒火山渣砌块本身质量及其影响墙体变形如温度、干燥收缩等性能和施工方面角度,分析了陶粒火山渣砌块填充墙在施工过程中存在的问题并提出了相应的防止措施。     

Full-scale dynamic testing of a steel frame building during construction

Full-scale testing of a six-story steel frame building with infill walls made primarily of autoclaved cellular concrete and curtain walls made of hollow core clay bricks using ambient and forced vibration methods are described in detail. The ambient vibration test took place in two stages of the construction—stage one, when only the frames and slabs where constructed, and stage two when all the walls were put in place. The forced vibration was carried out when some of the walls were constructed. The results from the two test methods are compared with each other and also with computer analysis results based on conventional design office assumptions for modeling. Dynamic characteristics of the structure including natural frequencies, damping ratios and mode shapes determined from the tests are presented. The effect of Autoclaved Cellular Concrete (ACC) block infill and partition walls on the dynamic properties and stiffness of the building are discussed in detail. The advantages of using ACC block walls as infill wall material for seismic regions are concluded.     

Temperature effects in buildings with panel walls

Temperature gradients in buildings with panel walls cause bending of the panels, force redistribution and shear between the walls, with possible excessive deformation of the joints and even separation of the walls. For prevention of these deformations and cracks in wall panels, as well as possible overloading of walls, appropriate design recommendations for different methods of connection between wall panels are proposed. The effects of heating and cooling of walls (which cause bending of the panels in the horizontal and vertical directions, as well as vertical shear between walls) are considered. Thermal considerations in the ultimate limit state of bearing walls are analysed.     

Comparison of retaining walls for basement construction in stiff clays

The selection of retaining walls supporting deep excavations for building basements on various factors such as soil types, permissible movements, construction methods, material and equipment availability etc. For excavations in soft soils, rigid walls such as diaphragm walls and contiguous bored pile walls are commonly used as they are more effective than the more flexible walls such as sheet pile walls, in limiting soil movements to an acceptable level. For excavations in stiff soils, the relative merits for the rigid and flexible walls become less clear. This paper compares the performance and cost-effectiveness of rigid and flexible walls. The relative merits between the rigid and flexible wall systems are discussed.     

外墙外保温的应用及其质量控制

在建筑施工中，发展外墙外保温技术已成为实现建筑节能的重要环节。概述了外墙外保温体系的特点，介绍了几种外墙外保温施工技术及其工艺流程，并从材料、设计和施工三个方面分析了外墙外保温施工的质量控制。     

某厂房承重墙体冻融损伤分析及处理

北方寒冷地区室内湿度较大的房屋当外墙采用砖墙时,因冻融对墙体的损伤作用而在承重墙体上产生劈裂裂缝,严重的甚至使一定厚度的墙体整体外鼓甚至脱落退出承载,这会大大降低外承重墙的承载能力,甚至有可能发生房屋倒塌事故。本文详细分析了某啤酒厂生产车间外墙产生损伤原因及危害,并提出原则性加固处理意见,供相关工程技术人员参考。     

水泥土防渗墙原位渗透试验方法研究

采用搅拌桩或者高压喷射方法施工水泥土连续墙用于防渗在水利水电等工程中多有应用,采用原位渗透试验方法测试防渗墙体抗渗性能是评价施工质量和效果的重要途径。目前在不同的规范中对测试方法均有相关的规定,但较少论及如何具体操作,且这些方法也在应用中存在各自的优缺点。结合工程经验,对相关方法的优缺点、适用性及方法的优化进行论述,并提出工程应用中的建议。     

Influence of toe restraint conditions on performance of geosynthetic-reinforced soil retaining walls using centrifuge model tests

Current design regulations most often require use of limit equilibrium methods for the internal stability analyses of geosynthetic-reinforced soil (GRS) walls. However, the limit-equilibrium based approaches generally over-predict reinforcement loads for GRS walls when comparing with measured data from full-scale instrumented walls under working stress conditions. Wall toe resistance has an important influence on the performance of GRS walls but is ignored in limit equilibrium-based methods of design. This paper reports centrifuge modelling of GRS walls which have different toe restraint conditions but are otherwise identical. The GRS wall models prepared in this study isolate the influence of wall toe resistance on the performance of walls. Based on measured data from four centrifuge wall model tests, a reduction in wall toe resistance (by reducing the interface shear resistance at the base of the wall facing or removing the soil passive resistance in front of the wall toe or both) induces larger maximum facing deformation and reinforcement strain and load. The results also demonstrate that the wall models with typical toe restraint conditions are most likely operated under working stress conditions while those with poor toe restraint conditions may experience (or be close to reach) a state of limit equilibrium.     

Geosynthetic-reinforced soil wall design

A number of diverse methods are available for the design of geosynthetic-reinforced soil walls. The various methods yield widely varying results. This study involved reviewing six published design methods, comparing design concepts; comparing the results of designs for various wall heights and geometries using each of the methods, and comparing two case histories of test walls which were tested to failure with the results predicted by each of the methods. It was found that the differences in the design results stem primarily from a significant disparity in defining allowable reinforcement strength and safety factors, and to a lesser degree, from discrepancies among the methods of analysis.     

反复荷载作用下混凝土多孔砖墙体受力性能试验研究

为系统研究混凝土多孔砖砌体结构的受力性能,并为编制CECS 257：2009《混凝土砖建筑技术规范》提供支持,对13片混凝土多孔砖墙体进行低周反复荷载试验,分析混凝土多孔砖墙体的破坏特征、承载能力、耗能能力及滞回特征等受力性能。试验结果表明：混凝土多孔砖墙体的破坏方式与普通砖墙体略有不同,主要表现为裂缝有可能产生在砖块内部,而不仅仅产生在砖块与砂浆的交界面上;墙体的承载力较高、耗能能力较好;竖向压应力对墙体的水平承载力影响较大;无构造柱墙体的水平承载力和耗能能力小于带构造柱墙体。基于试验结果,提出了地震作用下混凝土多孔砖墙体受剪承载力及变形能力的计算方法,并给出了混凝土多孔砖墙体的恢复力模型。图10表6参11